Metrix OX9302-BUS, Руководство пользователя

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Functional Description
21
b) from the screen
Click at top right in the screen, on the Time Base zone (see opposite).
Description below of the Y(t) - Y(f) - XY display modes
1. Y(t): temporal view
of a waveform
Settings from 1ns to 200s
No averaging
Averaging coeff.
2
Averaging coeff.
4
Averaging coeff.
16
Averaging coeff.
64
Selection of a coefficient in order to calculate an average on the
samples displayed: this can be used for example to attenuate the
random noise observed in a signal.
For the averaging coefficient to be taken into account in the
representation of the signal, the "Repetitive signal" option must be
selected.
The calculation is done using the following formula:
Pixel N = Sample*1/Averaging rate + Pixel N-1
(1-1/Averaging rate):
Sample Value of the new sample acquired at abscissa t
Pixel N Ordinate of the pixel at abscissa t on the screen,
at instant N
Pixel N-1 Ordinate of the pixel at abscissa t on the screen,
at instant N-1
Vector A vector is plotted between samples.
Envelope The minimum and maximum observed at each horizontal position on
the screen are displayed. Use this mode to display a variation in time or
of amplitude, or a modulation.
The entire
acquisition
The whole of the acquisition (100,000 samples) is displayed on the
screen and a vector is plotted between
samples. Use this mode to
display all details of the acquisition. This function can be used on a
memory or on a curve already acquired.
Increased time resolution of a trace for a periodic signal.
If this option is checked, the signal can be averaged.

For time bases finer than 100µs/div. (without active zoom mode), the signal displayed
is reconstituted from several acquisitions. The time resolution can be as fine as 40ps.

If the signal is not repetitive, do use not this option. The time resolution will then be
±1ns.
If this choice is checked, reconstruction of the signal can take a rather long time.
The following parameters influence this time:

the time base

the frequency of recurrence of the trigger

the activity of the Averaging mode
During this reconstruction, the signal must be stable (amplitude, frequency, waveform).
To speed up the reconstruction following a change in the signal, stop the acquisition, then
restart: Stop/Run.